The long, winding river that is the human digestive tract is prone to all manner of diseases, from the merely irritable to the decidedly deadly. All fall under the purview of the H.H. Chao Comprehensive Digestive Disease Center, an internationally lauded assemblage of doctors, pooled knowledge and technology devoted to gastrointestinal health gathered under one roof at the UCI Medical Center campus, in Orange.

According to executive director Dr. Kenneth Chang, who holds the Vincent and Anna Kong Chair in Gastrointestinal Endoscopic Oncology – the nation’s only such endowed chair – the ethos that permeates the CDDC is “innovation fueled by compassion.” Both qualities contribute to the center’s often-pioneering approach to curing cancers and improving patient outcomes.

Some of the most common, potentially deadly and hard-to-treat cancers are in the digestive system, in parts of the body generally ignored unless a tumor lodges there – such as the esophagus.

In an understatement, Dr. Jason Samarasena, CDDC gastroenterologist and associate clinical professor of medicine, notes that “removing your esophagus is sort of a really big deal.”

The tube connecting the throat and stomach really doesn’t look its best on a stainless steel tray. That’s where it’s removed to, however, in the standard surgical procedure for esophageal tumors. The cancerous sections are excised, and when the shortened esophagus is reinstalled, the stomach typically is relocated into the rib cage to be attached to it.

“Even our esophageal surgeons tell me the only thing worse than getting esophageal cancer is getting surgery for esophageal cancer,” Samarasena says.

A successful surgery means one gets to live and return to a relatively normal life. But that’s not what Samarasena’s surgery-bound patients are focused upon, he says: “They’re worried about being cut open, feeding tubes, the risks and the monthslong recovery.”

That was the case with Alwyn Kong (no relation to Vincent and Anna Kong) when a tumor was found in his esophagus in 2018. He was referred to UCI Health and put on the list for surgery. Kong looked into what that entailed and, he says, “went from shock to disbelief to freaking out, imagining every worst possible outcome.”

What he didn’t imagine was waking up from an exploratory endoscopic ultrasound to have Samarasena tell him he was a likely candidate for an outpatient procedure called endoscopic submucosal dissection, which involves no external surgery, organ relocation or long recovery.

“This was all an unknown to me, but Dr. Sam was so enthusiastic about it that I decided it was the way to go,” recalls Kong, now 59.

With ESD, the patient is sedated and an endoscope accesses the esophagus via the mouth. The tumor is injected with a fluid to lift it and define its borders. In a successful operation, the growth is endoscopically excised and the area is tested for clean margins.

Kong was back home within 12 hours of the ESD and says that within a week, he was fully recovered “and eating tostada salads again.”

Adapting Procedures for Success

It was fortuitous for Kong that he wound up at the CDDC, one of the first, foremost and most experienced facilities in the U.S. performing ESDs. The ESD procedure was developed in Japan and has been adopted in other East Asian countries, where a high incidence of stomach cancer dovetails with endoscopy’s efficacy at removing gastric tumors.

Chang became interested in the procedure in the late 1990s and sent one of his fellows to Japan to study it. Along with wanting to provide an alternative for U.S. stomach cancer patients, he saw the potential for treating other cancers.

In the years since, Chang has overseen the expansion of ESD to treat Barrett’s esophagus (a cancer precursor), as well as early esophageal and colon cancers. To date, the CDDC has performed more than 100 such procedures, and it’s a major teaching facility for spreading the technique.

While Chang believes the word “pioneer” should be reserved for the physicians in Asia who developed the process, “we have been deeply involved in how these technologies are being refined and iterated. We assess various devices and ask ‘Why can’t we do this with it, or combine this with that? How can we make this better, faster, easier?’”

He’s taken an endoscope to new areas as well. “I developed the ability to examine the liver by an endoscopic ultrasound,” Chang says. “From inside the stomach, I can do a liver biopsy that’s less invasive than coming from the outside, and I can directly measure the pressure on the key vessels going into and leaving the liver to determine if it’s progressing toward cirrhosis. That’s a UCI first.”

Early Detection Is Essential

While Chang and the CDDC are expanding the endoscope’s utility into other regions, there is one limiting caveat for its use in removing esophageal cancer: The tumor has to be caught in its early stages, as was the case with Kong. If it has spread more than 500 microns (about the thickness of two standard playing cards) into the esophageal wall, the invasive chest-opening surgery is likely needed.

Chang was especially pleased when early detection allowed him to help a 68-year-old patient, Rubin Molina, who had come to the CDDC with a recurrence of esophageal cancer, after undergoing a surgical excision at another facility two years earlier.

“Surgery the second time wasn’t an option. There wasn’t enough left of his esophagus to cut it safely, and he’d already maxed out on radiation,” Chang says. “I did the ESD on him, and even though the tumor was down to the muscle, we were able to get it all. Three years later, he’s still cancer-free and living a normal life.”

While they’re seeking endoscopic solutions for removing deeper tumors, CDDC experts are also working to boost early detection of esophageal cancer. They’re currently testing a device called a Cytosponge, developed at the University of Cambridge, that enables a 10-minute screening in a doctor’s office.

“I’m really excited about it,” Samarasena says. “Right now, the only way to test for esophageal cancer is to put an endoscope down your throat while you’re sedated, which takes up your whole day. The Cytosponge is a capsule with a sponge in it attached to a string. You swallow it, the capsule dissolves in your stomach, and when the sponge is pulled out, it collects about 500,000 cells that are sent to a lab. If the sample is positive, then you have an endoscopy done.”


“A cancer patient is a team effort. With all of us being in the same location, there’s a constant communication between us. I travel to places where the surgeons and GI doctors are not even on the same campus, let alone the same floor.”


UCI gastroenterologist Dr. Jason Samarasena describes cancer treatment options, including the leading-edge ESD procedure, using a model of the human esophagus. Photo: UCI Health

Constructed for Collaboration

Along with such advances, Chang and Samarasena credit the collaborative nature of the CDDC for their patient successes, noting that there are few such facilities in which all the disciplines dealing with gastrointestinal disease are together.

“A cancer patient is a team effort,” Samarasena says. “With all of us being in the same location, there’s a constant communication between us. I travel to places where the surgeons and GI doctors are not even on the same campus, let alone the same floor.”

Chang says that even the look of their building – which was redesigned and expanded by 24,000 square feet two years ago – has a purpose.

“It was built with training in mind,” he says. “Everywhere you look there’s glass. We wanted it to be a window for the world to see in: What’s new? What are the cutting-edge, breakthrough technologies? We have teaching workshops nearly every week. We want to serve our community, the nation and the world by being a place where physicians can come and be exposed to the newest ways to help others.”

Kong has remained cancer-free since his surgery in 2018. His work – as a vice president of human resources in the resort industry – has since taken him to Boca Raton, Florida. “But there is no way I’m going to change my doctors,” Kong says. “When I have an appointment, I fly back for it. I couldn’t be more delighted with the care I’ve received.”

Molina, who’d had a recurrence of esophageal cancer, is similarly appreciative. “The [first] surgery left me feeling like I’d been through my own autopsy. I was hospitalized for almost a month. It took three months to start feeling even a little bit like myself,” he says.

“When the cancer came back, I couldn’t have faced that again. So you can’t imagine how grateful I am for the ease of the ESD and Dr. Chang’s care. My daughter was so impressed with their compassion that she’s studying to become a nurse.”

Patients aren’t the only parties who are pleased. Says Samarasena: “ESD is by far the most rewarding procedure I’ve learned in my life. It’s very mentally and technically taxing, taking hours longer than a standard endoscopic procedure. But when a patient comes out of it and I get to say ‘Hey, we got it all,’ you just can’t imagine how gratifying that is.”

Chang concurs: “I’m blessed to have the experience and the technology and to be in this environment where innovation is supported. Being able to offer what we do and make a difference in people’s lives? I get crazy satisfaction from that.”